1. Technical Field
The invention generally relates to an overdriving apparatus of a display panel and an overdriving method thereof, and more particularly, to an overdriving apparatus generating an overdriving frame according to an overdriving table of response times of different liquid crystals and an overdriving method thereof.
2. Related Art
With the advancement of display technology, three-dimensional display devices (3D display device) capable of displaying 3D images gradually become main research topics in the display device field. FIG. 1A is a schematic diagram illustrating playing of a three-dimensional display apparatus. As illustrated in FIG. 1A, 3D display devices are usually used in corporation with shutter glasses. Besides, during a process of playing images, when odd number images IMG11, IMG13 . . . reach the stable status, a left eye of an observer is covered by the shutter glasses so that just a right eye is able to see the image. Then, when even number images IMG12, IMG14 . . . reach the stable status, the right eye of the observer is covered by the shutter glasses so that just the left eye is able to see the image. Accordingly, the left eye and the right eye of the observer are able to respectively receive images at different angles, and the images are thereby combined to achieve the 3D effect.
In order to ensure the images reach the stable status, the present 3D display devices mostly drive the liquid crystal display panel by an overdriving method, so as to speed up a response time of the liquid crystals. FIG. 1B is a structure schematic diagram illustrating an overdriving apparatus of a conventional three-dimensional display apparatus. Referring to FIG. 1B, the overdriving apparatus 100 includes a memory unit 110 and an overdriving circuit 120. The memory unit 110 stores a present display frame IMG11, and transmits a previous display frame IMG12 to the overdriving circuit 120. The overdriving circuit 120 stores an overdriving table. Accordingly, the overdriving circuit 120 looks up the overdriving table according to the previous display frame IMG12 and the present display frame IMG11, and generates the overdriving display frame according to the query result.
It is to be noted that, the overdriving table stored in the overdriving circuit 120 is established based upon response times of the liquid crystals on a middle scanning line of the liquid crystal display panel. However, the liquid crystal penal is driven in a sequential scanning approach. That is, there are different requirements on time for liquid crystals located on different scanning lines to reach the stable status. Therefore, under a condition where the conventional overdriving circuit 120 is based upon the response times of the liquid crystals on the middle scanning line, the generated overdriving frame would cause too strong transitions of the liquid crystals on an upper area of the display panel and insufficient transitions of the liquid crystals on a lower area of the display panel. Accordingly, the 3D imaged watched by the observer would have a problem of a cross-talk between stereo images, and thereby lower the 3D image quality.